I'm looking at building an insulated trunk line from my keezer to the first floor. The trunk line would carry 3 product lines and a recirculating coolant line. The run length would be about 9 feet out of the keezer (it is almost directly below where I want the taps on the next floor). I keep my keezer at about 38 degrees, and would keep the coolant and pump inside the keezer, not a seperate freezer. Anybody have any experience with keezer temperature coolant cooling the trunk lines? Hate to go through the effort and not have coolant lines that are cool enough to keep the product lines cool.

Fill the "trunk line" will the coolant, instead of just having a coolant line.

Or, easier yet, insulate the trunk line (2-3" PVC?) and run a return pvc line back to the keezer, so that both ends of the PVC loop are inside the keezer. Put a supply and exhaust fan on the ends of the pipe and forget the water and pumps. If you did pick up some heat in the PVC run, you can always lower your keezer temp a few degrees to compensate.

I was looking at those lines, but concerned that because my coolant wasn't going to be below freezing, it may have trouble cooling through the plastic lines. I'm thinking copper coolant lines will be more effective. Is your coolant in your keezer or in a freezer? How does it do keeping the lines cool?